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The increase in the level of iron concentration in drinking water due to natural and anthropogenic activities has become a major problem imposing a severe risk to human wellness. Mining and associated activities have qualitative and quantitative effects on the water regimes in and around the mines. People residing in the mining areas of Odisha, India, confronted a typical problem of iron contamination in water. Almost 60% of the surface water and 50% of the drinking water constitutes iron ions more than the permissible limit established by World Health Organization (W.H·O) i.e. 0.3 mg/L has been noted. Excessive iron accumulation may cause severe health problems such as hemochromatosis, diseases related to the heart and central nervous system, cirrhosis of the liver, diabetes, nausea, etc. Available literature has been incorporated on iron remediation by adsorption technology. This technology has been widely accepted because it offers economic and environmental benefits such as low cost, availability, profitability, ease of operation, and high removal efficacy. Thus the feasibility of activated carbon prepared from various agro-wastes for eradication of iron ions by batch and fixed-bed adsorption has been critically reviewed in this paper.

The authors developed a nanocomposite using polypropylene (PP) and graphene nanoplatelets (GNPs) with a melt mixing method. Virgin PP was filled with three sets of GNPs with a fixed thickness (15 nm) and surface area (50–80 m2/g). The selected H-type GNPs had three different sizes of 5, 15 and 25 µm. The nanocomposites were made by loading GNPs at 1, 2 and 3 wt.%. Mechanical analysis was carried out by performing tensile, flexural and impact strength tests. The crystalline, micro-structural, thermal and dynamic mechanical properties were assessed through XRD, FESEM, PLM, DSC, TGA and DMA tests. It was observed that all three types of GNPs boosted the mechanical strength of the polymer composite. Increasing the nanofiller size decreased the tensile strength and the tensile modulus, increased the flexural strength and flexural modulus, and increased the impact strength. Maximum tensile strength (≈41.18 MPa) resulted for the composite consisting 3 wt.% H5, whereas maximum flexural (≈50.931 MPa) and impact (≈42.88 J/m) strengths were observed for nanocomposite holding 3 wt.% H25. Graphene induced the PP’s crystalline phases and structure. An improvement in thermal stability was seen based on the results of onset degradation (TD) and melting (Tm) temperatures. Graphene increased the crystallization (Tc) temperatures, and acted like a nucleating agent. The experimental analysis indicated that the lateral size of graphene plays an important role for the nanocomposite’s homogeneity. It was noted that the small-sized GNPs improved dispersion and decreased agglomeration. Thus overall, small-sized GNPs are preferable, and increasing the lateral size hardly establishes feasible characteristics in the nanocomposite.